The Cytokine and Cell Phenotype Core will provide special expertise in the detection and measurement of cytokins and the analysis and purification of cell populations. This Core will combine the expertise of Drs. Nancy Street and Louis Picker to provide state-of-the-art technology in the analysis of murine and human cytokines and cell populations. Analysis of cytokines, both at protein and mRNA levels, will continue to be a major focus. It will provide: 1) expertise in analyzing human and mouse cytokines, 2) quantitation of cytokines via ELISA and/or bioassay, 3) procurement and preparation of reagents required for mono- specific cytokine assays, 4) quality of control, and 5) guidelines and training of SDRC investigators in the establishment of human cytokine assays. Particular emphasis will be given to the development of human cytokine analysis. To this end, ELISAs and bioassays specific for human cytokines are being developed. Additionally, to meet immediate needs, this core has expanded to include Cell Phenotyping and Flow Cytometry which will be directed by Dr. Picker. His laboratory will provide expertise and special reagents for analysis and purification of cell populations in suspension by providing: 1) high resolution multiparameter flow cytometric analysis of both cell surface and intracellular antigens, with particular emphasis on cytokines in secretion inhibited cells, and cell cycle (DNA) and apoptosis analysis, 2) multiparameter cell sorting, 3) training in these techniques, 4) consultation for experimental set-u and data analysis, and 5) assistance in the acquisition and/or production of special relevant reagents. Additionally, quantitative PCR analysis of human and murine cytokines is possible through use of internal standard DNA constructs generated within the labs of Drs. Picker and Street, respectively. In summary, expansion of this Core Laboratory will provide immediate support for human cytokine analysis and cell phenotyping while maintaining all currently available murine cytokine support.